Question

I’m trying to increase the size of a particular textview from within the app. I would like to do it via a menu item selection but am having problems. I have tried the following:

@Override
public boolean onCreateOptionsMenu(Menu menu) 
{
    // Create an options menu for the activity
    super.onCreateOptionsMenu( menu );

    incrseTxtMenu = menu.add( 0,4,0,"Increase Text Size" );
    incrseTxtMenu.setIcon( R.drawable.ic_menu_plus );
    incrseTxtMenu.setOnMenuItemClickListener( new MenuItem.OnMenuItemClickListener() 
    {
        @Override
        public boolean onMenuItemClick(MenuItem item) 
        {
            // handler.sendMessage( handler.obtainMessage() );
            TextView tempTxt = getTextView();
            tempTxt.setTextSize( 25 );

            return true;
        }
    });

    return true;
}

But this is throwing a null pointer exception. I also tried just using intro.setTextSize() but it throws the same error. How can I access the textview from within this menu item?

**Update

//Method used to fetch the textview
public TextView getTextView()
{
    return intro;
}

And the error from log cat:

AndroidRuntime FATAL EXCEPTION: main
java.lang.NullPointerException
at android.omni.Artist_activity$1.handleMessage( Artist_activity.java:32 )

Also btw – I’m trying to use a handler to update the GUI – am I correct in assuming that this is necessary right?

**Update 2 XML CODE

   <?xml version="1.0" encoding="utf-8"?>
    <ScrollView
      xmlns:android="http://schemas.android.com/apk/res/android"
      android:id = "@+id/tab_one_top_level"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent">

      <LinearLayout
      android:orientation = "vertical"
      android:layout_width="fill_parent"
      android:layout_height="fill_parent">

      <TextView

    android:id = "@+id/faq_Intro"
    android:layout_width = "wrap_content"
    android:layout_height = "wrap_content"
    android:text = "@string/faq_Intro"
    android:typeface = "monospace"
    android:textStyle = "bold"
    android:paddingBottom = "12dp"

      />

      <TextView

    android:id = "@+id/faq_Intro_Info"
    android:layout_width = "wrap_content"
    android:layout_height = "wrap_content"
    android:text = "@string/faq_Intro_Info"
    android:textSize = "10dp"
    android:typeface = "monospace"
    android:textStyle = "bold"

      />

      </LinearLayout>
</ScrollView>

Any thoughts?

My Code Solution

@Override
public boolean onCreateOptionsMenu(Menu menu) 
{
    // Create an options menu for the activity
    super.onCreateOptionsMenu( menu );

    incrseTxtMenu = menu.add( 0,1,0,"Increase Text Size" );
    incrseTxtMenu.setIcon( R.drawable.ic_menu_plus );

    decrseTxtMenu = menu.add( 0,2,0,"Decrease Text Size" );
    decrseTxtMenu.setIcon( R.drawable.ic_menu_negate );

    return true;

}

@Override
public boolean onOptionsItemSelected(MenuItem item) 
{
    // Increase size menu item
    if( item.getItemId() == 1 )
    {
        intro.setTextSize( myIntroSize += 5 );
        introInfo.setTextSize( myIntroInfoSize += 5 );

    }
    // Derease size menu item
    else if( item.getItemId() == 2 )
    {
        intro.setTextSize( myIntroSize -= 5 );
        introInfo.setTextSize( myIntroInfoSize -= 5 );
    }
    return true;
}

The onCreate() method simply initialises the textview as before. Oh and the values of myIntroSize and myIntroInfoSize can be whatever you want.

Answer 1

Please try the following code and tell me if it works. I don’t know what is wrong, it’s just based on a few hunches –

    @Override
public boolean onCreateOptionsMenu(Menu menu) 
{
    // Create an options menu for the activity
    super.onCreateOptionsMenu( menu );

    incrseTxtMenu = menu.add( 0,4,0,"Increase Text Size" );
    incrseTxtMenu.setIcon( R.drawable.ic_menu_plus );
    return true;
}


@Override
public boolean onOptionsItemSelected(MenuItem item) {
    if(item.getItemId() == 4){
         TextView tempTxt =  (TextView)findViewById( R.id.faq_intro);
            tempTxt.setTextSize( 25 );
    }

}